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The timeline of radio lists within the history of radio, the technology and events that produced instruments that use radio waves and activities that people undertook. Later, the history is dominated by programming and contents, which is closer to general history .
The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed theory and inventions in what became radio. Radio development began as "wireless telegraphy". Later radio history increasingly involves matters of broadcasting.
The hot comb was an invention developed in France as a way for women with coarse curly hair to achieve a fine straight look traditionally modeled by historical Egyptian women. [44] However, it was Annie Malone who first patented this tool, while her protégé and former worker, Madam C. J. Walker, widened the teeth. [45]
Beginning in the late 1840s, women were employed as landline telegraph operators, sending and receiving Morse code messages. Early radio communication, then called "wireless telegraphy", was developed in the late 1800s, and also initially communicated using Morse code.
The first practical radio transmitters and receivers invented in 1894–1895 by Guglielmo Marconi used radiotelegraphy. [5] It continued to be the only type of radio transmission during the first few decades of radio, called the "wireless telegraphy era" up until World War I , when the development of amplitude modulation (AM) radiotelephony ...
Radio waves were first predicted by the theory of electromagnetism that was proposed in 1867 by Scottish mathematical physicist James Clerk Maxwell. [5] His mathematical theory, now called Maxwell's equations, predicted that a coupled electric and magnetic field could travel through space as an "electromagnetic wave".
Ray, William B. FCC: The Ups and Downs of Radio-TV Regulation (Iowa State University Press, 1990) Rosen, Philip T. The Modern Stentors; Radio Broadcasting and the Federal Government 1920–1934 (Greenwood, 1980) Settel, Irving. A Pictorial History of Radio (1960) Sies, Luther F. Encyclopedia of American Radio: 1920–1960 (McFarland, 2nd ed. 2 ...
Guglielmo Marconi, who built the first radio receivers, with his early spark transmitter (right) and coherer receiver (left) from the 1890s. The receiver records the Morse code on paper tape Generic block diagram of an unamplified radio receiver from the wireless telegraphy era [4] Example of transatlantic radiotelegraph message recorded on paper tape by a siphon recorder at RCA's New York ...